Hi guys hoping to get some advice I have a 2010 fiesta 1.25 zetec and it keeps blowing the wiper fuse and burning out the wiper motor its had 3 motors and a wiper switch changed in the last 2 months the wiper linage has also been stripped clean and greased. Wiring loom has been checked and all appears fine. Has anyone seen this issue before I'm running out of ideas as what the cause of this problem is. 

Check the GEM (fusebox) for water ingress damage

Thanks Dave I've checked the fuse box all looks god I gave it a shot of connect cleaner just to be on the safe side. Does anyone know is there a wiper relay in the fiesta or are the wipers controlled by the BCM

5 minutes ago, Lawson86 said:

Does anyone know is there a wiper relay in the fiesta or are the wipers controlled by the BCM

No wiper relay, they are controlled directly by the BCM.

The only thing that can be causing the motor to draw excess current and to blow the fuse is excess load on the motor. I would very carefully remove and check all the linkage and drive shafts  to the wiper arms. Something is either catching/jamming the operation of the wipers, or the linkage is seizing up.

Just as an after thought this problem hasn't just started after replacing the wiper blades, has it ?

If you get Forscan you can perform a test of the BCM (if it's a BCM and not still a GEM on this model)

If you've changed the motor and the switch then it has to be the control or a wiring fault somewhere

Ok so I've stripped the linkage clean and greased and refitted rechecked wiring loom and the GEM all ok. Forecast isn't picking up any codes but launch is pulling B1c45. Fuse is blowing even when the motor and switch is disconnected. I'm thinking BCM problem. What are your thoughts 

On 5/5/2023 at 5:00 PM, Lawson86 said:

Ok so I've stripped the linkage clean and greased and refitted rechecked wiring loom and the GEM all ok. Forecast isn't picking up any codes but launch is pulling B1c45. Fuse is blowing even when the motor and switch is disconnected. I'm thinking BCM problem. What are your thoughts 

Possibly.

Definitely check for damaged wiring to motor

Ya stripped back the flexi conduit all the way back to the bulk head and I've belled out the cable between themselves and the body only one I'm getting continuity from is the earth. When I turn ignition on I'm getting continuity between ground and park position 

On 5/2/2023 at 6:21 PM, Lawson86 said:

and burning out the wiper motor its had 3 motors

Speaking as an electrical engineer, there are only two possibly ways to burn out a motor.

1. Over voltage
2. Mechanically over loaded

Since the voltage of the car must be remaining less than 14.9V otherwise you would have lots of other equipment failing, then that just leaves mechanical overload.

The fuse blowing is a different matter. There has to be excess current being drawn.

1. This could be that the wiper motor is being mechanically overloaded.
2. There is damaged wiring after the fuse and before the motor
3. There is an internal fault with the GEM, after the fuse but before the connection to the external wiring.

If the fuse is blowing with the motor disconnected then that can not be the cause of the fault. The speed at which the fuse blows will give an indication of the severity of the fault. It takes approximately two and a half times the rated current to instantaneously blow the fuse. So to blow a 20 Amp fuse immediately would take 50A

With the motor disconnected and the fuse removed use a multimeter and measure the resistance of the output side of the fuse holder to earth. It should be infinity. With the motor connected I'd expect 5 to 10 ohms as the motor has quite a low resistance.